Predict conditions under which $Al$ might be expected to reduce $MgO$.

Which metal is most difficult to be extracted from its oxide?

Choose the correct option with reference to the following statements:
$(1)$ Pig iron is produced at a temperature of $1270 \ K$.
$(2)$ Pig iron contains $4 \%$ carbon.
$(3)$ Pig iron cannot be cast into a variety of shapes.
$(4)$ Pig iron contains small amounts of impurities like $P, S, Si, Mn$.

Which reaction from the following occurs at $2000 \ K$ in the blast furnace for the extraction of iron?

The oxidising and reducing agents respectively for the cyanide extraction of silver from argentite ore are

According to the following Ellingham diagram,$A$ reduces $BO_{2}$ when the temperature is